"Signature field(s) detected" in Adobe reader

I found it quite annoying that a green banner showed up in  Adobe reader every time I compiled a pdflatex file. To prevent this green banner from showing up, I found the instruction in this link (http://try67.blogspot.com/2013/05/acrobatreader-disable-sign-pane.html) which suggests a registry trick to set "HKLM\SOFTWARE\Policies\Adobe\(product name)\(version)\FeatureLockdown\cServices\bEnableEchoSignDetection" to 0. Unfortunately the key was not there on my laptop. I had to create the key and then the value by hand. Note that the latter should be created as a DWORD.

Reduce size of PDF files with embedded JPEG

I found this fantastic feature of ghostscript:

gswin64c -sDEVICE=pdfwrite -dNOPAUSE -dBATCH -dPDFSETTINGS=/ebook -sOutputFile=C:newFile.pdf C:originalFile.pdf

Sources:
http://www.itechies.net/blog/archives/1764
http://www.alfredklomp.com/programming/shrinkpdf/

Optomechanics project revisted

1. The two-time correlator of the collective polarization/inversion operator does not scale with the square of the atom numbers. It scales with N instead, since we assume there is no correlation between two different atoms.

2. When applying the Wierner-Khinckin theorem with operators, do not make the Fourier transform of an operator A^\dagger(w) =[A(-w)]^*. Keep all the operators as they are but perform the identity for their prefactors if needed.

Using box.net as the dav server in Zotero

Check the workaround in
http://forums.zotero.org/discussion/20351/

"Possible workaround: The problem might just be that there's a delay before uploaded files are available, which would be a problem for the server verification but possibly not for a normal Zotero file sync. You can try going to about:config in the Firefox address bar (or clicking "Open about:config" from the Advanced pane of the preferences in Standalone) and setting extensions.zotero.sync.storage.verified to true, which will override the server verification and let you try to sync. No guarantees, obviously."

The setting in Zotero is https://www.box.com/dav/zotero.

Matlab: Fatal error on startup: Failure loading desktop class

Updating jre messed up matlab configure file again. Removing classpath.txt in ~ fixed the problem.

MacPro CD/DVD tray problem in ubuntu

I was able to eject a cd/dvd in unbuntu 9 from the command line using "eject." Somehow it doesn't work anymore in 11.10, neither does "eject /dev/cdrom" or "eject cdrom" work. By going into the /dev directory, I found that cdrom is just a link for sr0 in my MacPro, and "eject /dev/sr0" did the job! There is also a sr1 which I thought was the 2nd tray in MacPro, but "eject /dev/sr1" didn't do anything.

Fix bcd the elegant way

Oh well, I messed up the bcd and the Win 7 installation CD didn't find the OS installed. Then I tried bootrec /rebuildbcd, which found one out of two installed OS, but it couldn't continue and complained that bcd is being used by another process.

I was about to give up but then found this post (http://neosmart.net/wiki/display/EBCD/Recovering+the+Windows+Bootloader+from+the+DVD)

bootrec.exe /fixmbr bootsect.exe /nt60 all /force

cd C:\boot
attrib -h -s BCD del BCD
bcdedit /createstore bcd.temp bcdedit.exe /store bcd.temp /create {bootmgr} /d "Windows Boot Manager" bcdedit.exe /import bcd.temp bcdedit.exe /set {bootmgr} device partition=C: bcdedit.exe /timeout 10 attrib -h -s bcd.temp del bcd.temp
 

bcdedit.exe /create /d "Microsoft Windows" /application osloader
 

bcdedit.exe should return a message with a GUID for the newly-created entry, something like this:
The entry {c0dfc4fa-cb21-11dc-81bf-005056c00008} was successfully created. 

Then use this number/entry and type 

bcdedit.exe /set {c0dfc4fa-cb21-11dc-81bf-005056c00008} device partition=C: bcdedit.exe /set {c0dfc4fa-cb21-11dc-81bf-005056c00008} osdevice partition=C: bcdedit.exe /set {c0dfc4fa-cb21-11dc-81bf-005056c00008} path \Windows\system32\winload.exe bcdedit.exe /set {c0dfc4fa-cb21-11dc-81bf-005056c00008} systemroot \Windows
bcdedit.exe /displayorder {c0dfc4fa-cb21-11dc-81bf-005056c00008}

In my case the XP is on C: and Win 7 on E:. However, the winload.exe is missing in the XP partition(?), so I had to try a second time and set all the "C:" above to "E:" which solved the problem.

Another thought: Maybe I should have changed the attribute of the bcd file and tried /rebuildbcd? Anyway, the problem is now fixed.

Updated: A similar but more complete guide was found on http://idoneitmyself.wordpress.com/2009/11/15/windows-7-suddenly-wont-boot-reboot-and-select-proper-boot-device-or-insert-boot-media-in-selected-boot-device-and-press-any-key-repairing-the-windows-7-bootloader/